P016

Geoacoustic Inversion Using SA in East China Sea Experiment

A0036 Shinya Matsumoto 5th Research Center,Technical Research and Development Institute, Japan Defense Agency

A0037 Kazuhiko Ohta 5th Research Center,Technical Research and Development Institute, Japan Defense Agency

A0038 Kouki Okabe 5th Research Center,Technical Research and Development Institute, Japan Defense Agency

A0039 Gaku Takei NEC Corporation

 

Information of the geoacoustic properties is very important to predict

the sound propagation in shallow water, but it is generally difficulty

to measure them directly. An experiment for studying those properties

acoustically was conducted in the shallow water of the East China Sea.

In the experiment, a hydraulic-type projector was towed by sending out

low-frequency continuous wave with a source level of 180 dB to 185 dB,

and the propagating sound was measured using a moored vertical line

array composed of 8 sensors. As a method for estimating the

geoacoustic properties, matched field processing (MFP) combined with

Simulated Annealing (SA) was employed. Correlation between the

measured and calculated pressure fields was totally taken over around

100 points in water column; these locations can be demonstrated to

affect efficiency and speed in SA.